Add galerie per concert

assets/css/main.css

@@ -507,11 +507,29 @@ footer {
     }
 }
 
+.galerie {
+    display: flex;
+    flex-direction: column;
+    gap: 20px;
+}
+
+.galerie-item {
+    background-color: white;
+    box-shadow: 0 0 16px #333;
+    border-radius: 8px;
+    padding: 8px;
+    width: 95%;
+    margin: 10px auto;
+}
+
+.galerie-item h2 {
+    text-align: center;
+}
+
 .galerie-table {
     columns: 3 300px;
     column-gap: 1.5rem;
-    width: 90%;
-    margin: 10px auto;
+    padding: 20px;
     line-height: 0;
 }